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Re: modules

On Sun, Oct 08, 2000 at 07:12:42PM +0500, nikkie21 wrote:
> hi
> i want to know that why we require special function   put_user   while
> copying data from kernel data segment  to user data segment.

So that if the user passes a bad pointer, the kernel doesn't fall on
its face. It used to do "verify_area" before dereferencing the pointer,
but in recent kernels, the verification is done using the CPU's MMU.
(Linux device drivers, Rubini, p 398).